Refrigeration evaporator



y 1955 c. H. WURTZ ETAL 2,712,736

REFRIGERATION EVAPORATOR Filed July 8, 1953 3 Sheets-Sheet l WW I LEW I 1/ Clifford/iWur/z BY Le/and H Grene/l The/r Attorney Jul 12, 1955 c. H. WURTZ ETAL 2,712,736 REFRIGERATION EVAPORATOR F/QZ JNVENTORS Clifford h. Wurfz BY Leland H. Grene/l 7' hair Attorney y 12, 1955 c. H. WURTZ ET AL 2,712,736

REFRIGERATION EVAPORATOR Filed July 8, 1955 3 Sheets-Sheet 5 I130 5' 5 n' u n n I130 11 n n 5 INVENTORS Clifford H. War/z Leland H Grene/l INEW The/i Attorney United States Patent 2,712,736 REFRIGERATION EVAPORATOR Application July 8, 1953, Serial No. 366,699 2 Claims. (Cl. 62-126) This invention relates to refrigerating apparatus and more particularly to a combination evaporator and accumulator and its method of manufacture.

It is an object of this invention to provide an improved method and apparatus for disengaging liquid refrigerant from refrigerant vapors and for accumulating the disengaged liquid in a roll-forged plate type evaporator.

The advantages of manufacturing evaporators by the roll-forging process have long been recognized but a number of problems presented themselves when it came to manufacturing roll-forged evaporators requiring accumulators or so-called header or boiler sections. The present known processes for manufacturing roll-forged evaporators make it impossible to conveniently form chambers of any appreciable size in the main body of a roll-forged evaporator. One of the reasons for this is that the pressures required to dilate the internal passages in the roll-forged evaporator are so great that it would be difficult, if not impossible, from a practical standpoint to dilate the larger passages without rupturing the walls thereof or unduly distorting the metal adjacent the larger passages. It is now present practice to confine the plate type evaporator between'two flat plates during the dilation process and to thus limit the distance which the plates are separated. This practice results in the formation of fiat walled refrigerant passages. If a fiat walled accumulator of any appreciable size were to be formed in an evaporator by conventional methods, the refrigerant pressures generated within the system would be sufiiciently great to cause the flat walls to bulge outwardly in use and thereby distort the evaporator. It is an object of this invention to form a fiat walled accumulator capable of with standing high pressures without any distortion.

Another object of this invention is to make it possible to form an accumulator as an integral part of a rollforged evaporator.

Another object of this invention is to make an accumulator which occupies a minimum amount of valuable space.

Still another object of this invention is to provide an improved accumulator and disengaging chamber in a roll-forged evaporator which may be formed simultaneously with the formation of the usual refrigerant passages.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings:

Figure 1 is a perspective view partly schematic showing the invention applied to a refrigerator;

Figure 2 is a perspective view showing the sheets used in manufacturing the combined evaporator and accumulator;

Figure 3 is a fragmentary side elevational view show 2,712,736 Patented July 12, 1955 ing the plate type evaporator and accumulator in the process of construction;

Figure 4 is a plan view of the evaporator and accumulator after the passages have been dilated but before the plate has been bent into the form shown in Figure 1;

Figure 5 is a fragmentary sectional view taken substantially on line 55 of Figure 4; and,

Figure 6 is a fragmentary sectional view taken substantially on line 66 of Figure 4 but adding the heavy backing plates used in the process of dilating the refrigerant passages.

Referring now to the drawing wherein a preferred embodiment of the invention has been shown, reference numeral 10 generally designates a conventional refrigerated cabinet having a food storage compartment 12 in which an evaporator 14 constructed in accordance with my invention is mounted. The cabinet includes the usual refrigerant liquefying compartment 16 in which a condenser 18 and a sealed motor-compressor unit 20 are mounted. For purposes of illustrating the invention, the evaporator 14 has been shown mounted in the upper portion of the food compartment in accordance with common practice.

The evaporator is made by the roll-forging method disclosed in Long application Ser. No. 151,591, filed March 24, 1950, now Patent No. 2,662,273 and Simmons application Ser. No. 289,729, filed May 24, 1952.

24 and 26 are first superimposed upon one another with a stop-weld material 28 applied to the face of one of the plates in a predetermined pattern. The plates preferably have an except where the plates stop-weld material. The

ground oyster shells, The roll-forging operation greatly forged together the internal passages of the plates are dilated by subjecting the same to a fluid pressure While the plates are confined between two flat dies 33 in the manner fully explained in said Long and Simmons applications. When the composite plate comes out from between the rollers and while it is being dilated, it is in the fiat shape whereas in its final form it is bent into the shape shown in Figure 1 and ends of the sheet are trimmed and suitable mounting holes are punched after the roll-forging operation.

As best shown in Figures 2 and 4 of the drawing, the pattern of the stop-weld material is such that tortuous refrigerant passages 34 are formed in the plate and these passages serve as the main refrigerant passages of the evaporator. The liquid refrigerant is fed into the passages 34 through the inlet line 36. At least vaporizes in the passages 34 whereby a mixture of liquid and vapor is fed into an in one side wall of the evapaccumulator section 40 is pro Wall of the evaporator and is connected in series with the section 38.

It will be noted that each accumulator section is in eifect a large flat chamber wherein a plurality of spaced provided between the opposite it possible to subject the accumulator to high internal pressures without danger of of the drawing. The edges or distorting the flat side Walls of the accu- The largest unsupported surface urine accumulator is not great enough to be distorted by the highest pressures encountered in a refrigerant evaporator.

Each of these accumulators is capable of storing an appreciable quantity of liquid. refrigerant therein and by virtue of the arrangement of the inlet and outlet to each "of the accumulators as well as the arrangement of the multiplicity of obstructions to the flow of refrigerant from the inlet of each accumulator to the outlet of the accumulator it serves as an'effective means for disengaging the. refrigerant. vapor from the liquidrefrigerant after the mixture of, refrigerant and vapor enter the accumulator.

By virtue of the fact. that the accumulator sections are formed in the vertical portions of the evaporator and by virtue of the fact that the incoming mixture of vapor and liquid refrigerant enters each accumulator adiacent the bottom thereof and is. required to follow a. tortuous path before leaving the upper portion of the accumulator it is obvious that the accumulator also serves very effectively to prevent slugs of liquid refrigerant from being carried along with bubbles of refrigerant. vapor passing upwardly through the liquid refrigerant in the accumulator.

While the form of embodiment of the invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted, as may come within the scope of the claims which follow.

What is claimed is as follows:

1. In a refrigerating system, a roll-forged evaporator having a refrigerant passage formed therein, one portion rupturing mulator.

of said refrigerant passage having an enlargement therein adjacent the outlet thereof arranged in a. vertical plane and serving as an accumulator chamber, said enlargement having relatively flat substantially parallel side walls spaced a distance substantially corresponding to the distance between the walls of said passage, said side walls being forge-welded together; at a plurality of spaced points so as to. prevent bulging of said walls when sub- T jected to high internal pressures.

2.. In a refrigerant system, a roll forged evaporator having a refrigerant passage formed therein, one portion of said refrigerant passage adjacent the outlet thereof having an enlargement therein arranged in a vertical plane and serving as an accumulator chamber, said enlargement having, side walls spaced a distance substantially corresponding to the distance between the walls of said passage, said side walls being forge-weldedrtogether at a plurality of. space points so as'to prevent bulging. of said side wallswhen subjected to high internal pressures, said enlargementhaving, a vertical extent and a horizontal extent several times as great as the distance between the walls of said enlargement.

References Cited in the file of this patent UNITED STATES PATENTS 

